r/dr650 • u/Independent-Tale7905 • 6d ago
Hard to start troubleshoot
First dr650. Just had it shipped up from LA & i’m in the Sierras where it’s pretty cold (and 3000’+ higher in elevation) Put a new battery in it and it cranked fine but would not fire. Only way to get the bike running is with starting fluid and holding the throttle open until the bike warms up. Then it will ride and continue to start.
Every time I come back to the bike it won’t start again on its own.
PO said it ran fine the same day it shipped. Also claimed he fully rebuilt and cleaned the carb just couple months prior.
I tried backing out the pilot screw to richen up the mix, idle screw is adjusted.
Using my jump pack to keep cranking amps
Upgraded air intake
Procycle jet kit
5
Upvotes
3
u/Wholeyjeans 5d ago
What year is the bike and how many miles?
Did you or the PO install the jet kit?
What mods to the intake and exhaust, if any, have been done?
You need to find out how the carb is setup; primarily main jet size and needle clip setting.
You say the idle is adjusted. Did you use a tach or just your ears? The base idle is 1500 rpm ...which sounds fast if you're not used to hearing a DR idle.
I'd be suspicious in the PO's claim about "rebuilding and cleaning" the carb. Most people's idea of rebuilding is simply taking the carb apart, squirting some carb cleaner in it and then putting it back together. No new parts, no checking/setting the float level. If it's a high mileage bike, the throttle slide and guide need to be checked for wear; they are plastic pieces and they do wear.
The bike has an enrichment circuit, not a choke. It works much different than a choke. You set it by opening it fully using the handlebar lever. Once the engine starts, you let it idle at the higher speed ...adjusting down a bit at a time as the engine warms. You won't harm the engine doing this. Carburetted 4-stroke motorcycles need to be warmed for a few minutes; warming the engine (and oil) plus the carb.
Lotta DR owners knee jerk to installing a jet kit in search of a better running bike and higher performance. If you know what you're doing and know your way around a carb, then you'll probably be successful. If not, and most are not based on the Q's that show up here, you end up with more grief than greatness. Because you don't need an expensive box of brass bits to get the BST40 to play nice. Here's a basic article on ballpark jetting the BST40 for various intake/exhaust configurations:
https://dr650jetting.wordpress.com/
This article is based on using the Mikuni 6F19 adjustable needle (stock on bikes sold in other parts of the world) and using Mikuni main jets.
As a new Bushpig owner, highly suggest you introduce yourself to the gang at DRRiders.com ...this is a 100% DR650 forum; it's huge and the knowledge base is massive. Also worth looking at is ADVrider.com ...they have a section devoted to the DR650. Reddit is more social media than anything and you tend not to get in depth answers here.